In general, electronic devices include portable communication devices, MP3 players, portable multimedia players (PMPs), and electronic books, and any suitable devices by which users can access various contents while carrying them.
If prices and functions of electronic devices are not significantly different, users may prefer to choose the ones having appealing designs. Thus, an outer appearance of an electronic device, that is, a design of a case will be a primary factor which influences a user to select the electronic device.
A metallic material may be used to make a case of an electronic device luxurious, but it is difficult to process the metallic material into a specific shape. That is, there are many difficulties in realizing a design of a desired shape with a metallic material. Moreover, when a case of an electronic device is formed of a metallic material, the portability of the electronic device is lowered due to the weight of the material. Thus, recently, a synthetic resin which can be easily formed and processed and has a light weight is mainly used as the material of a case of an electronic device. When a case of an electronic device is injection-molded by using a synthetic resin, a non-conductive metallic material such as tin may be deposited on a surface of an injection preform to realize a metallic texture.